1. Field of the Invention
The present invention relates to a photographic processing apparatus having a film developing section, a printer section for printing an image recorded on a film onto printing paper, a printing paper developing section, and the like, and in particular to a photographic processing apparatus wherein the printer section is provided with a scanner for measuring density and other properties of negative film so as to automatically adjust exposure based on the measured data.
2. Description of the Related Art
With advancing photographic processing techniques, photographic processing apparatus are now popular which can perform continuous processing of film development, printing, and printing paper development. In some photographic processing apparatus, a continuous printing process is performed by linking a transport path in a printer section for printing an image onto a printing paper and a transport path in a developing apparatus for developing the printing paper. In some other photographic processing apparatus, a transport path in a film developing section, a transport path in a printer section, and a transport path in a printing paper developing section are all linked together.
In the film developing section, an undeveloped film is conveyed by using a leader and is sequentially passed at an appropriate processing rate through processing solution tanks containing processing solutions such as developer, fixer and the like suited for physicochemical properties of the film and then through a drying section, thereby developing the film. In the printer section, a negative film is set in a negative film mask, and printing paper on an exposure stage is exposed to light emitted from a light source, thereby exposing an image onto the printing paper.
In the printing paper developing section, the exposed printing paper is conveyed by means of rollers, guides and the like and sequentially is passed at an appropriate processing rate through processing solution tanks containing processing solutions such as developer, fixer and the like suited for physical properties of the printing paper and a drying section using warm air.
In the developing sections, photosensitive materials, i.e. the film and the printing paper are transported in a zigzag course through the processing solution tanks so as to lengthen their path within the processing solutions, thereby improving efficiency of development and decreasing the size of the photographic processing apparatus.
In the printer section, a scanner or the like is used to automate frame feed and exposure adjustment for the negative film. The printing paper is pulled out from a magazine loaded with roll printing paper and cut to a predetermined size, and thus cut printing paper is fed to the exposure stage, thereby improving work efficiency.
Conventional photographic processing apparatus are classified into two types according to arrangement of the printer section and the printing paper developing section. In the first type of photographic processing apparatus, the printer section and the printing paper developing section are lined on a common plane, thereby making the conveying path for a photosensitive material straight. Because of the straight conveying path and an associated simple structure, a photographic processing apparatus of this type can be fabricated in subassemblies, and the fabricated subassemblies can be combined at the time of installation. This facilitates transport and maintenance. When the film developing section is included in the photographic processing apparatus, the film developing section, the printer section, and the printing paper developing section are lined in the order of photographic processing.
In the second type of photographic processing apparatus, the printer section is disposed above the printing paper developing section. Because of integrated arrangement of these two sections, this type can be rendered compact. When the film developing section is included in the photographic processing apparatus, the film developing section and the printing paper developing section are arranged side by side, and the printer section is disposed above the printing paper developing section. In the aforesaid two types, the film developing section, the printer section, and the printing paper developing section are arranged such that the conveying paths of film and printing paper extend on a single plane.
In the printer section of the photographic processing apparatus capable of performing the aforesaid continuous processing, light from a light source is applied to a developed negative film and an image on the film for printing is focused on the printing paper through a lens. Density and color balance of the negative film depend on photographic conditions. For obtaining photographs with good image reproducibility, density and color corrections are needed to adjust light intensity and color balance.
When an operator performs the exposure adjustment manually, he/she should have ample experience and skilled techniques because the exposure adjustment is a quite difficult work to perform, as it involves determining density and color balance by observing on the negative film an image which is reverse in light intensity and color to a subject. To automate processing work and allow even those operators having little experience to obtain prints of the same quality, photographic processing apparatus are fabricated in which a printer is provided with a scanner for automatically correcting density and color.
The scanner scans an image on the negative film from the side opposite to a scanner light source to obtain photometric data regarding patterns, density, and colors. The photometric data is compared with reference values to calculate exposure correction data. Based on the exposure correction data, optimum exposure conditions are obtained. Under the optimum exposure conditions, an exposure light source, YMC (yellow-magenta-cyan) filters, and a shutter are controlled for printing. Thus, the printer section using the scanner requires an exposure light source and a scanner light source. Some conventional photographic processing apparatus have an exposure light source and a scanner light source in the printer section, and some other conventional photographic processing apparatus have one light source used for both exposure and scanning.
When there is a great difference between the quantity of light required for image exposure and the quantity of light required for the scanner, it is beneficial to prepare an exposure light source and a scanner light source independently of each other. When the exposure light source and the scanner light source are independently prepared, it is necessary to match printing and scanning conditions using light sources having the same tone, but this practice has the advantages that exposure control and scanning control are simple and that processing capability is high.
To increase accuracy of exposure adjustment, using the same light source for exposure and scanning is advantageous. This method reduces costs associated with the printer section and contributes toward decreasing the size of the apparatus. When the negative film is moved frame by frame for alternate scanning and printing, this method involves steps of adjusting the quantity of light, opening/closing a lens shutter, and alternately retreating the scanner and lens. When a plurality of frames on the negative film are continuously scanned before initiating printing, this method involves such an operation that the negative film is once advanced for scanning, then retreated, and then advanced again for printing.
The conventional photographic processing apparatus described above are arranged only in consideration of the linkage between conveying paths of apparatus sections. As a result, the conveying paths are mutually dependent, and thus apparatus sections are not completely independent of one another. In such photographic processing apparatus, any section cannot be changed or modified in accordance with a required processing capability, because possible combinations of the film developing section, the printer section, and the printing paper developing section are limited.
In particular, since the conveying path between the printer section and the printing paper developing section lies on the same line, no space is available for mounting additional devices such as an index printer, i.e., an ink Jet or another type printer for printing indices on printing papers, and an enveloper for automatically enveloping the negative film, thus preventing the entire photographic process, ending with an enveloping process, from being fully automated.
The use of a single light source as both an exposure light source and a scanning light source is suited for reducing the size of the printer section, but involves complicated control over film feed in printing and scanning with a resultant deterioration during processing capability.